We show that the distinction between Self and Other, 'us' and 'them,' or in-group and out-group, affects significantly economic and social behavior. In a series of experiments with approximately 200 Midwestern students as our subjects, we found that they favor those who are similar to them on...

This paper exploits longitudinal employer-employee matched data from the U.S. Census Bureau to investigate the contribution of worker and firm reallocation to changes in earnings inequality within and across industries between 1992 and 2003. We find that factors that cannot be measured using...